I bought this headphone twice, because I like it a lot. They're good for the money, not perfect but definitely great. First, I'll talk about build quality and comfort, then efficiency and sound. (and also a bonus category of how moddable they are)
TL;DR review:
9.5/10 overall. Sound/value easily 10/10. Comfort 9/10. Build quality 8/10. Does not need amp, benefits from one. They're easy to mod for beginner DIYers.
1. Build Quality: 4.5/5
I'd say the build is the only part that shows they're a cheap headphone, don't get me wrong -- they're solidly built but they creak a lot on your head. They aren't prone to scratches or chips, which is probably...

Incredible soundstage is the best thing about these full-size cans. Unmodded, they are merely good. The "Top Pop" mod makes the bass tighten up quite a bit, stopping any "boom." It really makes these come alive. Very 3D.

These are shockingly good for $56. The build quality is as good as most pairs costing more than twice as much. And, the sound is clear and defined without being harsh or fatiguing. Although, I thought it was a little lacking in the low-end department. (I'm not a basshead. But, I do like deep, tight, defined bass.) I also like their simple, full-size, non-folding style. Their size and shape make them great for home or office use. But, I doubt if you wanna be carrying these around with you.
Pros:
-Clear and defined mids and highs, without the harshness in the upper mids that can often accompany such clarity.
-No distortion on the low-end. No fartiness or...